title: Potential of the propolis as storage medium to preserve the viability of cultured human periodontal ligament cells: an in vitro study.
abstract: OBJECTIVE
  In vitro experiments were carried out to evaluate the potential of propolis, a natural resin known for its wide therapeutic window, as storage medium to preserve the viability of cultured human periodontal ligament (PDL) cells.
  
  
  METHODS
  Primary cultures of human PDL cells were subjected to either independent exposure of propolis (2.5%, 5.0%, 10.0%, and 20.0%), Hank's balanced salt solution (HBSS), milk (0.5%), artificial saliva, Dulbecco's modified Eagle's medium (DMEM) or combination of propolis 10% + DMEM, propolis 20% + DMEM for 30 min to 24 h at 37 °C. Cell viability was assessed using standard endpoints i.e., tetrazolium bromide salt (MTT), neutral red uptake, and trypan blue dye exclusion assay.
  
  
  RESULTS
  In general, combinations of propolis 10% + DMEM, propolis 20% + DMEM, and DMEM alone were found to be better than other media used in this study. The difference in the potentials of these media to maintain the cell viability reached to the statistically significant levels by 24 h, when compared with other media used viz., propolis 2.5% (P < 0.01), propolis 5.0% (P < 0.05), propolis 10.0% (P < 0.05), propolis 20.0% (P < 0.001), HBSS (P < 0.001), and milk (P < 0.01). Trypan blue dye exclusion assay could be recorded the most sensitive among all the assays selected to study the cell viability of PDL cells.
  
  
  CONCLUSIONS
  Study indicates that combinations of propolis 10% + DMEM, propolis 20% + DMEM, and DMEM alone are equally good as storage media of choice to keep PDL cells viable during extra-alveolar period up to 24 h. Other more readily available medium such as milk may serve as appropriate alternative storage medium for shorter time periods i.e., up to 12 h.
authors.affiliation: Department of Conservative Dentistry & Endodontics, CSM Medical University, India.
authors.forename: Payal
authors.initials: P
authors.lastname: Saxena
authors.forename: Vandana Aditya
authors.initials: VA
authors.lastname: Pant
authors.forename: Kulvindar Kaur
authors.initials: KK
authors.lastname: Wadhwani
authors.forename: Mahendra Pratap
authors.initials: MP
authors.lastname: Kashyap
authors.forename: Saurabh Kumar
authors.initials: SK
authors.lastname: Gupta
authors.forename: Aditya Bhushan
authors.initials: AB
authors.lastname: Pant
mesh_terms: D000818:Animals; D018929:Cell Culture Techniques; D002470:Cell Survival / Q000187:drug effects; D004396:Coloring Agents; D003470:Culture Media; D006801:Humans; D007552:Isotonic Solutions / Q000494:pharmacology; D008422:Materials Testing; D008892:Milk; D009499:Neutral Red; D019188:Organ Preservation Solutions / Q000494:pharmacology*; D010513:Periodontal Ligament / Q000166:cytology* / Q000187:drug effects; D011429:Propolis / Q000494:pharmacology*; D012464:Saliva, Artificial / Q000494:pharmacology; D013048:Specimen Handling; D013696:Temperature; D013778:Tetrazolium Salts; D013844:Thiazoles; D013997:Time Factors; D014343:Trypan Blue
chemical_list: D004396:Coloring Agents; D003470:Culture Media; C072670:Hanks Balanced Salt Solution; D007552:Isotonic Solutions; D019188:Organ Preservation Solutions; D012464:Saliva, Artificial; D013778:Tetrazolium Salts; D013844:Thiazoles; D009499:Neutral Red; D011429:Propolis; C022616:thiazolyl blue; D014343:Trypan Blue